export default {
	props: {
		localdata: {
			type: [Array, Object],
			default() {
				return []
			},
		},
		spaceInfo: {
			type: Object,
			default() {
				return {}
			},
		},
		collection: {
			type: String,
			default: '',
		},
		action: {
			type: String,
			default: '',
		},
		field: {
			type: String,
			default: '',
		},
		orderby: {
			type: String,
			default: '',
		},
		where: {
			type: [String, Object],
			default: '',
		},
		pageData: {
			type: String,
			default: 'add',
		},
		pageCurrent: {
			type: Number,
			default: 1,
		},
		pageSize: {
			type: Number,
			default: 500,
		},
		getcount: {
			type: [Boolean, String],
			default: false,
		},
		getone: {
			type: [Boolean, String],
			default: false,
		},
		gettree: {
			type: [Boolean, String],
			default: false,
		},
		manual: {
			type: Boolean,
			default: false,
		},
		value: {
			type: [Array, String, Number],
			default() {
				return []
			},
		},
		modelValue: {
			type: [Array, String, Number],
			default() {
				return []
			},
		},
		preload: {
			type: Boolean,
			default: false,
		},
		stepSearh: {
			type: Boolean,
			default: true,
		},
		selfField: {
			type: String,
			default: '',
		},
		parentField: {
			type: String,
			default: '',
		},
		multiple: {
			type: Boolean,
			default: false,
		},
		map: {
			type: Object,
			default() {
				return {
					text: 'text',
					value: 'value',
				}
			},
		},
	},
	data() {
		return {
			loading: false,
			errorMessage: '',
			loadMore: {
				contentdown: '',
				contentrefresh: '',
				contentnomore: '',
			},
			dataList: [],
			selected: [],
			selectedIndex: 0,
			page: {
				current: this.pageCurrent,
				size: this.pageSize,
				count: 0,
			},
		}
	},
	computed: {
		isLocalData() {
			return !this.collection.length
		},
		isCloudData() {
			return this.collection.length > 0
		},
		isCloudDataList() {
			return this.isCloudData && !this.parentField && !this.selfField
		},
		isCloudDataTree() {
			return this.isCloudData && this.parentField && this.selfField
		},
		dataValue() {
			let isModelValue = Array.isArray(this.modelValue)
				? this.modelValue.length > 0
				: this.modelValue !== null || this.modelValue !== undefined
			return isModelValue ? this.modelValue : this.value
		},
		hasValue() {
			if (typeof this.dataValue === 'number') {
				return true
			}
			return this.dataValue != null && this.dataValue.length > 0
		},
	},
	created() {
		this.$watch(
			() => {
				var al = []
				;[
					'pageCurrent',
					'pageSize',
					'spaceInfo',
					'value',
					'modelValue',
					'localdata',
					'collection',
					'action',
					'field',
					'orderby',
					'where',
					'getont',
					'getcount',
					'gettree',
				].forEach((key) => {
					al.push(this[key])
				})
				return al
			},
			(newValue, oldValue) => {
				let needReset = false
				for (let i = 2; i < newValue.length; i++) {
					if (newValue[i] != oldValue[i]) {
						needReset = true
						break
					}
				}
				if (newValue[0] != oldValue[0]) {
					this.page.current = this.pageCurrent
				}
				this.page.size = this.pageSize

				this.onPropsChange()
			}
		)
		this._treeData = []
	},
	methods: {
		onPropsChange() {
			this._treeData = []
		},

		// 填充 pickview 数据
		async loadData() {
			if (this.isLocalData) {
				this.loadLocalData()
			} else if (this.isCloudDataList) {
				this.loadCloudDataList()
			} else if (this.isCloudDataTree) {
				this.loadCloudDataTree()
			}
		},

		// 加载本地数据
		async loadLocalData() {
			this._treeData = []
			this._extractTree(this.localdata, this._treeData)

			let inputValue = this.dataValue
			if (inputValue === undefined) {
				return
			}

			if (Array.isArray(inputValue)) {
				inputValue = inputValue[inputValue.length - 1]
				if (
					typeof inputValue === 'object' &&
					inputValue[this.map.value]
				) {
					inputValue = inputValue[this.map.value]
				}
			}

			this.selected = this._findNodePath(inputValue, this.localdata)
		},

		// 加载 Cloud 数据 (单列)
		async loadCloudDataList() {
			if (this.loading) {
				return
			}
			this.loading = true

			try {
				let response = await this.getCommand()
				let responseData = response.result.data

				this._treeData = responseData

				this._updateBindData()
				this._updateSelected()

				this.onDataChange()
			} catch (e) {
				this.errorMessage = e
			} finally {
				this.loading = false
			}
		},

		// 加载 Cloud 数据 (树形)
		async loadCloudDataTree() {
			if (this.loading) {
				return
			}
			this.loading = true

			try {
				let commandOptions = {
					field: this._cloudDataPostField(),
					where: this._cloudDataTreeWhere(),
				}
				if (this.gettree) {
					commandOptions.startwith = `${this.selfField}=='${this.dataValue}'`
				}

				let response = await this.getCommand(commandOptions)
				let responseData = response.result.data

				this._treeData = responseData
				this._updateBindData()
				this._updateSelected()

				this.onDataChange()
			} catch (e) {
				this.errorMessage = e
			} finally {
				this.loading = false
			}
		},

		// 加载 Cloud 数据 (节点)
		async loadCloudDataNode(callback) {
			if (this.loading) {
				return
			}
			this.loading = true

			try {
				let commandOptions = {
					field: this._cloudDataPostField(),
					where: this._cloudDataNodeWhere(),
				}

				let response = await this.getCommand(commandOptions)
				let responseData = response.result.data

				callback(responseData)
			} catch (e) {
				this.errorMessage = e
			} finally {
				this.loading = false
			}
		},

		// 回显 Cloud 数据
		getCloudDataValue() {
			if (this.isCloudDataList) {
				return this.getCloudDataListValue()
			}

			if (this.isCloudDataTree) {
				return this.getCloudDataTreeValue()
			}
		},

		// 回显 Cloud 数据 (单列)
		getCloudDataListValue() {
			// 根据 field's as value标识匹配 where 条件
			let where = []
			let whereField = this._getForeignKeyByField()
			if (whereField) {
				where.push(`${whereField} == '${this.dataValue}'`)
			}

			where = where.join(' || ')

			if (this.where) {
				where = `(${this.where}) && (${where})`
			}

			return this.getCommand({
				field: this._cloudDataPostField(),
				where,
			}).then((res) => {
				this.selected = res.result.data
				return res.result.data
			})
		},

		// 回显 Cloud 数据 (树形)
		getCloudDataTreeValue() {
			return this.getCommand({
				field: this._cloudDataPostField(),
				getTreePath: {
					startWith: `${this.selfField}=='${this.dataValue}'`,
				},
			}).then((res) => {
				let treePath = []
				this._extractTreePath(res.result.data, treePath)
				this.selected = treePath
				return treePath
			})
		},

		getCommand(options = {}) {
			/* eslint-disable no-undef */
			let db = uniCloud.database(this.spaceInfo)

			const action = options.action || this.action
			if (action) {
				db = db.action(action)
			}

			const collection = options.collection || this.collection
			db = db.collection(collection)

			const where = options.where || this.where
			if (!(!where || !Object.keys(where).length)) {
				db = db.where(where)
			}

			const field = options.field || this.field
			if (field) {
				db = db.field(field)
			}

			const orderby = options.orderby || this.orderby
			if (orderby) {
				db = db.orderBy(orderby)
			}

			const current =
				options.pageCurrent !== undefined
					? options.pageCurrent
					: this.page.current
			const size =
				options.pageSize !== undefined
					? options.pageSize
					: this.page.size
			const getCount =
				options.getcount !== undefined
					? options.getcount
					: this.getcount
			const getTree =
				options.gettree !== undefined ? options.gettree : this.gettree

			const getOptions = {
				getCount,
				getTree,
			}
			if (options.getTreePath) {
				getOptions.getTreePath = options.getTreePath
			}

			db = db
				.skip(size * (current - 1))
				.limit(size)
				.get(getOptions)

			return db
		},

		_cloudDataPostField() {
			let fields = [this.field]
			if (this.parentField) {
				fields.push(`${this.parentField} as parent_value`)
			}
			return fields.join(',')
		},

		_cloudDataTreeWhere() {
			let result = []
			let selected = this.selected
			let parentField = this.parentField
			if (parentField) {
				result.push(`${parentField} == null || ${parentField} == ""`)
			}
			if (selected.length) {
				for (var i = 0; i < selected.length - 1; i++) {
					result.push(`${parentField} == '${selected[i].value}'`)
				}
			}

			let where = []
			if (this.where) {
				where.push(`(${this.where})`)
			}

			if (result.length) {
				where.push(`(${result.join(' || ')})`)
			}

			return where.join(' && ')
		},

		_cloudDataNodeWhere() {
			let where = []
			let selected = this.selected
			if (selected.length) {
				where.push(
					`${this.parentField} == '${
						selected[selected.length - 1].value
					}'`
				)
			}

			where = where.join(' || ')

			if (this.where) {
				return `(${this.where}) && (${where})`
			}

			return where
		},

		_getWhereByForeignKey() {
			let result = []
			let whereField = this._getForeignKeyByField()
			if (whereField) {
				result.push(`${whereField} == '${this.dataValue}'`)
			}

			if (this.where) {
				return `(${this.where}) && (${result.join(' || ')})`
			}

			return result.join(' || ')
		},

		_getForeignKeyByField() {
			let fields = this.field.split(',')
			let whereField = null
			for (let i = 0; i < fields.length; i++) {
				const items = fields[i].split('as')
				if (items.length < 2) {
					continue
				}
				if (items[1].trim() === 'value') {
					whereField = items[0].trim()
					break
				}
			}
			return whereField
		},

		_updateBindData(node) {
			const { dataList, hasNodes } = this._filterData(
				this._treeData,
				this.selected
			)

			let isleaf = this._stepSearh === false && !hasNodes

			if (node) {
				node.isleaf = isleaf
			}

			this.dataList = dataList
			this.selectedIndex = dataList.length - 1

			if (!isleaf && this.selected.length < dataList.length) {
				this.selected.push({
					value: null,
					text: '请选择',
				})
			}

			return {
				isleaf,
				hasNodes,
			}
		},

		_updateSelected() {
			let dl = this.dataList
			let sl = this.selected
			let textField = this.map.text
			let valueField = this.map.value
			for (let i = 0; i < sl.length; i++) {
				let value = sl[i].value
				let dl2 = dl[i]
				for (let j = 0; j < dl2.length; j++) {
					let item2 = dl2[j]
					if (item2[valueField] === value) {
						sl[i].text = item2[textField]
						break
					}
				}
			}
		},

		_filterData(data, paths) {
			let dataList = []
			let hasNodes = true

			dataList.push(
				data.filter((item) => {
					return (
						item.parent_value === null ||
						item.parent_value === undefined ||
						item.parent_value === ''
					)
				})
			)
			for (let i = 0; i < paths.length; i++) {
				let value = paths[i].value
				let nodes = data.filter((item) => {
					return item.parent_value === value
				})

				if (nodes.length) {
					dataList.push(nodes)
				} else {
					hasNodes = false
				}
			}

			return {
				dataList,
				hasNodes,
			}
		},

		_extractTree(nodes, result, parent_value) {
			let list = result || []
			let valueField = this.map.value
			for (let i = 0; i < nodes.length; i++) {
				let node = nodes[i]

				let child = {}
				for (let key in node) {
					if (key !== 'children') {
						child[key] = node[key]
					}
				}
				if (
					parent_value !== null &&
					parent_value !== undefined &&
					parent_value !== ''
				) {
					child.parent_value = parent_value
				}
				result.push(child)

				let children = node.children
				if (children) {
					this._extractTree(children, result, node[valueField])
				}
			}
		},

		_extractTreePath(nodes, result) {
			let list = result || []
			for (let i = 0; i < nodes.length; i++) {
				let node = nodes[i]

				let child = {}
				for (let key in node) {
					if (key !== 'children') {
						child[key] = node[key]
					}
				}
				result.push(child)

				let children = node.children
				if (children) {
					this._extractTreePath(children, result)
				}
			}
		},

		_findNodePath(key, nodes, path = []) {
			let textField = this.map.text
			let valueField = this.map.value
			for (let i = 0; i < nodes.length; i++) {
				let node = nodes[i]
				let children = node.children
				let text = node[textField]
				let value = node[valueField]

				path.push({
					value,
					text,
				})

				if (value === key) {
					return path
				}

				if (children) {
					const p = this._findNodePath(key, children, path)
					if (p.length) {
						return p
					}
				}

				path.pop()
			}
			return []
		},
	},
}
